/*
 * Copyright 2007-2008 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package jsr203.nio.file.attribute;

import java.io.IOException;
import jsr203.nio.file.FileRef;

/**
 * A file attribute view that supports reading or updating the owner of a file.
 * This file attribute view is intended for file system implementations that
 * support a file attribute that represents an identity that is the owner of
 * the file. Often the owner of a file is the identity of the entity that
 * created the file.
 *
 * @since 1.7
 */

public interface FileOwnerAttributeView
    extends FileAttributeView, UserPrincipalLookupService
{
    @Override
    FileOwnerAttributeView bind(FileRef obj);

    @Override
    FileOwnerAttributeView bind(FileRef obj, boolean followLinks);

    /**
     * Read the file owner.
     *
     * <p> It it implementation specific the file owner can be a {@link
     * UserPrincipal#isGroup() group}.
     *
     * @return  the file owner
     *
     * @throws  UnsupportedOperationException
     *          If not following links, the file is a link, and the implementation
     *          does not support reading the owner of a symbolic link
     * @throws  IllegalStateException
     *          If the attribute view is not bound, or if bound to an object
     *          that is not open for reading
     * @throws  IOException
     *          If an I/O error occurs
     * @throws  SecurityException
     *          In the case of the default provider, a security manager is
     *          installed, and it denies {@link
     *          RuntimePermission}<tt>("accessUserInformation")</tt> or its
     *          {@link SecurityManager#checkRead(String) checkRead} method
     *          denies read access to the file.
     */
    UserPrincipal getOwner() throws IOException;

    /**
     * Updates the file owner.
     *
     * <p> It it implementation specific the file owner can be a {@link
     * UserPrincipal#isGroup() group}. To ensure consistent and correct behavior
     * across platforms it is recommended that this method should only be used
     * to set the file owner to a user principal that is not a group.
     *
     * @param   owner
     *          The new file owner
     *
     * @return  this attribute view
     *
     * @throws  UnsupportedOperationException
     *          If not following links, the file is a link, and the implementation
     *          does not support updating the owner of a symbolic link
     * @throws  IllegalStateException
     *          If the attribute view is not bound, or if bound to an object
     *          that is not open for writing
     * @throws  IOException
     *          If an I/O error occurs, or the {@code owner} parameter is a
     *          group and this implementation does not support setting the owner
     *          to a group
     * @throws  SecurityException
     *          In the case of the default provider, a security manager is
     *          installed, and it denies {@link
     *          RuntimePermission}<tt>("accessUserInformation")</tt> or its
     *          {@link SecurityManager#checkWrite(String) checkWrite} method
     *          denies write access to the file.
     */
    FileOwnerAttributeView setOwner(UserPrincipal owner)
        throws IOException;
}
